69142721 has 2 divisors, whose sum is σ = 69142722. Its totient is φ = 69142720.

The previous prime is 69142693. The next prime is 69142783. The reversal of 69142721 is 12724196.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67831696 + 1311025 = 8236^2 + 1145^2 .

It is a cyclic number.

It is not a de Polignac number, because 69142721 - 2¹⁸ = 68880577 is a prime.

It is equal to p_4070579 and since 69142721 and 4070579 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (69142321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34571360 + 34571361.

It is an arithmetic number, because the mean of its divisors is an integer number (34571361).

Almost surely, 2^69142721 is an apocalyptic number.

It is an amenable number.

69142721 is a deficient number, since it is larger than the sum of its proper divisors (1).

69142721 is an equidigital number, since it uses as much as digits as its factorization.

69142721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 32.

The square root of 69142721 is about 8315.2102198321. The cubic root of 69142721 is about 410.4391902893.

The spelling of 69142721 in words is "sixty-nine million, one hundred forty-two thousand, seven hundred twenty-one".